At high altitudes, such as those encountered by commercial flights and space stations, these cosmic rays could be killer.

Experts believe a big enough flare could wipe out satellites and power lines, bringing an end to modern civilisation as we know it as electronic devices are rendered useless.

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Obama issued the stark warning in an executive order calling on his government to come up with a plan to deal with devastating space weather.

In the document he writes: “Extreme space weather events – those that could significantly degrade critical infrastructure – could disable large portions of the electrical power grid, resulting in cascading failures that would affect key services such as water supply, healthcare, and transportation.

“Space weather has the potential to simultaneously affect and disrupt health and safety across entire continents.

“Successfully preparing for space weather events is an all-of-nation endeavor that requires partnerships across governments, emergency managers, academia, the media, the insurance industry, non-profits, and the private sector.”